Installation for the regulation of the angular velocity of a shaft



Jan. 17,1933. I A E E 1,894,562

INSTALLATION FOR THE REGULATION OF THE ANGULAR VELOCITY OF A SHAFT Filed Jan. 31. 1930 2 Sheets-Sheet l Jan. 17, 1933. M J A E ETAL 1,894,562

INSTALLATION FOR THE'REGULATION OF THE ANGULAR VELOCITY OF A SHAFT Filed Jan. 31, 1950 2 Sheets-Sheet 2 m m QflF WIIMIII lf iilllk- Marina: Jaaabus J4 we FoaZo/ Verna/Zen Nicolaas flmkany Jo/zmmes l aor/roew JNVENTORS.

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Patented Jan. 17, 1933 UNITED STATES PATENT OFFICE MARINUS J'AOOBUS JANSEN. 'ROELOF VEBMEULEN, AND NICOLAAS ANTHONY J'O- HANN ES VOORHOEVE, OF EINDHOVEN, NETHERLANDS, ASSIGNORS TO N. V. PHILDB' GLOEILAMPENFABRIEKEN, OF EINDHOVEN, NETHERLANDS, A LIMITED LIABILITY COMPANY OF THE NETHERLANDS INSTALLATION FOR THE REGULATION OF THE ANGULAB VELOCITY OF A SHAFT Application filed January 31, 1930, Serial No. 425,052, and in the Netherlandn Iarch 9, 1929.

The invention relates to an installation for exactly regulating the number of revolutions of a shaft. In some cases, for example in driving the shaft of the turntable 5 of a gramophone, it is very important to lreep the angular velocity of this shaft constant within narrow limits as otherwise the reproduction does not remain perfect. The invention suggests a relatively simple means which permits the ohtention of an exact regulation in a reliable manner.

Accerdin to he invention, with the shaft coupleo wo electric generators of which one acts in the input circuit of an amplifier whose output circuit comprises the field winding of the second generator which acts as a bralre-dyna fhe i must worlr as much as inertia and according to hould preferably be made resistance amplifier having slOllS between the coupled ration follows hereinafter to the accompanying drawepresent, by way of example, in to respectively two embodiments invention to sh are secured the armatures of a motor /L a brake-dynamo RD and a speed adjusting dynamo TD. The latter is provided with a separately excited field Winding hut also he constituted by a magnet or by shunt dynamo although the use of the latter has "proved to he less recommendable.

The minus terminal oi the speed adjusting dynamo is connected through a galvanic battery Q to the control grid of a thermionic valve 1 whereas the plus terminal is connected to the cathode of this valve.

The anode circuit of the valve I comprises ill a resistance ll, the ends of which are con stages may be used (with some restrictions further to be mentioned in connection, for example, with Fig. 2), said number being de termined for each particular case by circumstances.

In the anode circuit of the last valve of the cascade is included the field winding l W of the brake-dynamo RD.

The working is as follows:

So long as the voltage of re mains from which the motor M is "fed and the oil the shaft El remain constant, the n -her of revolutions oi; the latter retains. e value which there is equilibrium h 76811 the va ricus couples acting on ti sl lit, however, this equilibriu in some way or other, the nit tions increases or decreases that the number oi revolution this case the terminal voltage o the speed adjusting dynamo increases *Mortionally owing to which the potential o he of valve consequently a ode current in the resistance ll, decrease. e diiderence between the ends of resistance ll, consequently decreases since these ends are connected to the nd to the cathode of the valve ll iner that the potential of the grid i that of the cathode end, the current in the resistance R increases. consequently the potential of the of valve lll decreases so that the anode current in decreases which causes the grid potential at the valve ll?" to rise.

Finally, the anode current of the final valve IV, consequently, increases and since the field winding VW is traversed by this cur rent, the antagonistic couple of the brakedynamo Bl) increases, the increase of the number of revolutions being thus counteracted.

The same remarks apply if the number of revolutions decreases.

With the arrangement of the valves I to IV as represented and described, it is evident that the grid potentials of these valves alternately increase and decrease. It follows that when the speed adjusting dynamo is connected to the valve I in such manner that at disturb l or of revolulet us we I till tive terminal of the direct current generator is connected to the cathode of the first amplifier' tube, and the positive terminal connected through a battery to the grid of said tube, the arrangement being otherwise the same as that in Fig. 1. I

However, when separate anode and filament current batteries are used, the coupling between the valves may also be such that the potentials of all the grids either increase or decrease. It is evident that in this case, one is consequently free in the choice of the numbcr of valves.

The above-described method of regulation has the advantage that in spite of considerable variations of the ,tension and/or the frequency of the mains and of the fluctuations of the load of the shaft itself, the number of revolutions of the latter is kept within very narrow limits. This shaft can therefore be used for driving devices which are extremely sensitive to variations of the number of revolutions, such, for example as gramophones, wire windings and spinning machines and others. For example, for a gramophone this drive may be effected by means of a worm W which is secured to the shaft.

However, since such transmissions may themselves give rise to irregularities in the number of revolutions of the shaft of the de-' vice which is driven, it may sometimes be advantageous to mount the speed adjusting dynamo (and if required also the brakedynamo) directly on the said shaft and consequently behind instead of before the transmission.

When applying the invention to the socalled talking films, that is, devices in which a cinematographic projector is driven synchronously with a gramophone, the brakedynamo may be utilized to furnish current to the various relays which are commonly uti-' lized with such a device, a constant and effective load of the brake-dynamo being thus obtained.

What we claim is:

1. An installation for regulating the angular velocity of a shaft, comprising a direct current generator, a second generator which acts as a brake dynamo, both generators being mechanically coupled to the said shaft, and an amplifier having an input and an output circuit, the first generator beingconnected to the input circuit of the said amplifier,

' and the field winding of the second generator messes sistance coupled amplifier, the other being connected through a battery to the grid of the said tube, and a brake dynamo mechanically'coupled to the said shaft, the exciting winding of which brake-dynamo is inserted in the output circuit of. the said amplifier.

3. An installation for maintaining constant the angular velocity of a shaft, comprising a dlrectcurrent generator mechanically coupled to said shaft, a resistance coupled amplifier having a number of tubes, the

anode of each tube of which is connected through a battery to the grid of the followmg tube one of the terminals of which generator is connected to the cathode of the first tube of the resistance coupled amplifier, the other being connected through a battery to the grid of the said tube, and a brake-dynamo mechanically connected to the. said shaft, the exciting winding of which dynamo is inserted in the output circuit of the said amplifier.

4. An installation for regulating the angular velocity of a shaft, comprising a direct current generator mechanically coupled to shaft, a resistance coupled amplifier, having an even number of tubes, the anode of each tube of which is connected through ,a battery to the grid of the following tube, the positive terminal of the said generator being connected to the cathode of the first tube of the amplifier, the negative terminal being connected through a battery to the grid of the said tube, and a brake-dynamo mechanically coupled to the said shaft, the exciting winding of said brake-dynamo being inserted in the output circuit of the said amplifier.

5. An installation for regulating the angular velocity of a shaft, comprising a direct current generator mechanically coupled to said shaft, a resistance coupled amplifier, having an odd number of tubes, the anode of each tube of which isconnected through .a battery to the grid of the following tube, the negative terminal of the said generator being connected to the cathode of the first tube of the amplifier, the positive terminal being connected through a battery to the grid of the said tube, and a brake-dynamo, mechanically coupled to the said shaft, the exciting Winding of said brake-dynamo being inserted in the output circuit of the said amplifier.

In testimony whereof we have signed our names to this specification.

MARINUS JACOBUS JANSEN. ROELOF VERMEULEN.

NICOLAAS ANTHONY .IOH ANNES VOORHOEVE 

